The government of Ethiopia has been implemented participatory forest management (PFM) program since 1990s, with twin policy goals of promoting sustainable forest management and improving livelihoods. However, the benefits of this program intervention for forest conservation and livelihoods are not systematically studied and well documented. This study assessed the contribution of PFM program to forest conservation and the livelihoods in Nono sele woreda, southwest of Ethiopia. Data were collected from 241 randomly selected households. A mixed research approach, which integrates household survey, focus group discussions, key informant interviews and field observations were used for this study. Quantitative data were analysed using the Statistical Package for Social Science (SPSS version 23).The findings revealed that improved forest conservation and socio-economic conditions of the local communities were observed after the implementation of PFM in the study area. Expansion of agriculture into forest areas and settlement in the forest has been reduced as reported by vast majority of the respondents 83.4% and 87.1% respectively, while secured right of access to non-timber forest products and household incomes were enhanced as reported by 84.2% and 63.1% of the respondents, respectively. In order to sustain the PFM program, there is a need to provide more tangible economic benefits and alternative income-generating activities to the local communities. Thus, we recommend that Oromia Forest and Wildlife Enterprise and other non-governmental organizations should work on forest and non-forest based livelihood activities.